Connectors with springs for holding, latching, or locking applications are widely available for use as mechanical connectors and for use in electrical applications. Typically a pin is inserted into a bore of a housing and a spring is used therebetween as a connector for holding, latching, or locking application. Holding typically implies a single groove application, either in the pin or the housing, in which the spring force and the friction force between the spring and either the housing or the pin removably secure the two components together. Latching implies insertion to connect with removal capability to disconnect, without destroying the spring. Locking implies insertion to connect but without removal capability to disconnect unless the spring is destroyed. Both latching and locking applications typically use a groove on the pin and a groove in the housing to secure a spring therebetween.
Implantable medical devices for providing electrical stimulation to body tissues, for monitoring physiologic conditions, and for providing alternative treatments to drugs are well known in the art. Exemplary implantable medical devices include implantable cardio defibrillators, pacemakers, and programmable neuro-stimulator pulse generators, which are collectively herein referred to as “implantable medical devices” or IMDs. These IMDs typically incorporate a hermetically sealed device enclosing a power source and electronic circuitry, also known as a “can” or a “can housing”. Connected to the sealed housing is a header assembly. The header assembly includes electrical contact elements that are electrically coupled to the electronic circuits or to the power source located inside the can via conductive terminals or leads. The header assembly provides a means for electrically communicating, via an external medical lead cable, between the electronic circuits or power source located inside the device and the actual stimulation point.
Industry wide standards have been adopted for, among other things, the dimensions, size, pin spacing, diameter, etc. for the receptacle and the medical lead cable. Furthermore, good electrical contact must be maintained during the life of the implantable medical device, and the medical lead cable for use with the IMD must not disconnect from the receptacle located in the header, yet be detachable for implanting and programming purposes and for replacing the IMD when necessary.
Although prior art connector contacts provide viable options for medical device manufacturers, the overall dimensions of existing receptacles pose manufacturing challenges. Among other things, placing stackable rings in between electrically insulating seals, positioning conductive contact elements in between conductive grooves for forming a receptacle and integrating the contact assembly into the IMD are difficult, costly and time consuming tasks.
Active implantable medical connectors have typically required serial arrays that allowed for several connections in a row. Examples of prior art connectors are disclosed in US Publication Nos. US2010/0233896 A1, US2008/0255631 A1 and US2008/0246231 A1, the contents of each of which are expressly incorporated herein by reference. As technology advances and new therapies require greater sophistication, the typical connection systems cannot support some of the new therapies that require high number of electrodes or connection nodes.